Based on the provided data what is the standard deviation of the VOO ETF total returns for the $3-$year period between $2021$ to $2023?$

$\backslash$table$[[$Year$,\backslash$table$[[$T$-$bill total$],[$return$]],\backslash$table$[[$S&P $500$ total$],[$return$]],\backslash$table$[[$VOO ETF total$],[$return$]]],[2023,4\mathrm{.}29\%,26\mathrm{.}29\%,26\mathrm{.}33\%$